Industrial systems demand semiconductors that are precise, flexibleand reliable. Linear Technology offers a broad line of high performanceanalog ICs that simplify system design with rugged devices featuringparameters fully guaranteed over the -40°C to 85°C temperature range.We back this up with knowledgeable applications support, LONG productlife cycles and superior on-time delivery.
上传时间： 2013-11-02
上传用户：xiaodu1124
This publication represents the largest LTC commitmentto an application note to date. No other application noteabsorbed as much effort, took so LONG or cost so much.This level of activity is justified by our belief that high speedmonolithic amplifiers greatly interest users.
标签： 高速放大器
上传时间： 2014-01-06
上传用户：wfl_yy
Sensors for pressure, load, temperature, acceleration andmany other physical quantities often take the form of aWheatstone bridge. These sensors can be extremely linearand stable over time and temperature. However, mostthings in nature are only linear if you don’t bend them toomuch. In the case of a load cell, Hooke’s law states that thestrain in a material is proportional to the applied stress—as LONG as the stress is nowhere near the material’s yieldpoint (the “point of no return” where the material ispermanently deformed).
上传时间： 2013-11-12
上传用户：墙角有棵树
Linear Technology’s high performance battery management ICsenable LONG battery life and run time, while providing precision charging control, constantstatus monitoring and stringent battery protection. Our proprietary design techniques seamlesslymanage multiple input sources while providing small solution footprints, faster charging and100% standalone operation. Battery and circuit protection features enable improved thermalperformance and high reliability operation.
上传时间： 2013-10-12
上传用户：yyq123456789
Alkaline batteries are convenient because they’re easy tofi nd and relatively inexpensive, making them the powersource of choice for portable instruments and devicesused for outdoor recreation. Their LONG shelf life alsomakes them an excellent choice for emergency equipmentthat may see infrequent use but must be ready to go on amoment’s notice. It is important that the DC/DC convertersin portable devices operate over the widest possiblebattery voltage range to extend battery run time, and thussave the user from frequent battery replacement.
上传时间： 2014-12-24
上传用户：569342831
TLC2543是TI公司的12位串行模数转换器，使用开关电容逐次逼近技术完成A/D转换过程。由于是串行输入结构，能够节省51系列单片机I/O资源；且价格适中，分辨率较高，因此在仪器仪表中有较为广泛的应用。 TLC2543的特点 （1）12位分辩率A/D转换器； （2）在工作温度范围内10μs转换时间； （3）11个模拟输入通道； （4）3路内置自测试方式； （5）采样率为66kbps； （6）线性误差±1LSBmax； （7）有转换结束输出EOC； （8）具有单、双极性输出； （9）可编程的MSB或LSB前导； （10）可编程输出数据长度。 TLC2543的引脚排列及说明 TLC2543有两种封装形式：DB、DW或N封装以及FN封装，这两种封装的引脚排列如图1，引脚说明见表1 TLC2543电路图和程序欣赏 #include<reg52.h> #include<intrins.h> #define uchar unsigned char #define uint unsigned int sbit clock=P1^0; sbit d_in=P1^1; sbit d_out=P1^2; sbit _cs=P1^3; uchar a1,b1,c1,d1; float sum,sum1; double sum_final1; double sum_final; uchar duan[]={0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,0x07,0x7f,0x6f}; uchar wei[]={0xf7,0xfb,0xfd,0xfe}; void delay(unsigned char b) //50us { unsigned char a; for(;b>0;b--) for(a=22;a>0;a--); } void display(uchar a,uchar b,uchar c,uchar d) { P0=duan[a]|0x80; P2=wei[0]; delay(5); P2=0xff; P0=duan[b]; P2=wei[1]; delay(5); P2=0xff; P0=duan[c]; P2=wei[2]; delay(5); P2=0xff; P0=duan[d]; P2=wei[3]; delay(5); P2=0xff; } uint read(uchar port) { uchar i,al=0,ah=0; unsigned LONG ad; clock=0; _cs=0; port<<=4; for(i=0;i<4;i++) { d_in=port&0x80; clock=1; clock=0; port<<=1; } d_in=0; for(i=0;i<8;i++) { clock=1; clock=0; } _cs=1; delay(5); _cs=0; for(i=0;i<4;i++) { clock=1; ah<<=1; if(d_out)ah|=0x01; clock=0; } for(i=0;i<8;i++) { clock=1; al<<=1; if(d_out) al|=0x01; clock=0; } _cs=1; ad=(uint)ah; ad<<=8; ad|=al; return(ad); } void main() { uchar j; sum=0;sum1=0; sum_final=0; sum_final1=0; while(1) { for(j=0;j<128;j++) { sum1+=read(1); display(a1,b1,c1,d1); } sum=sum1/128; sum1=0; sum_final1=(sum/4095)*5; sum_final=sum_final1*1000; a1=(int)sum_final/1000; b1=(int)sum_final%1000/100; c1=(int)sum_final%1000%100/10; d1=(int)sum_final%10; display(a1,b1,c1,d1); } }
上传时间： 2013-11-19
上传用户：shen1230
第五章 Keil C51库函数参考 C51强大功能及其高效率的重要体现之一在于其丰富的可直接调用的库函数，多使用库函数使程序代码简单，结构清晰，易于调试和维护，下面介绍C51的库函数系统。 1. 第一节 本征库函数(intrinsic routines)和非本征证库函数 C51提供的本征函数是指编译时直接将固定的代码插入当前行，而不是用ACALL和LCALL语句来实现，这样就大大提供了函数访问的效率，而非本征函数则必须由ACALL及LCALL调用。 C51的本征库函数只有9个，数目虽少，但都非常有用，列如下： _crol_,_cror_：将char型变量循环向左(右)移动指定位数后返回 _iror_,_irol_：将int型变量循环向左(右)移动指定位数后返回 _lrol_,_lror_：将LONG型变量循环向左(右)移动指定位数后返回 _nop_： 相当于插入NOP _testbit_： 相当于JBC bitvar测试该位变量并跳转同时清除。 _chkfloat_： 测试并返回源点数状态。 使用时，必须包含#inclucle 一行。 如不说明，下面谈到的库函数均指非本征库函数
上传时间： 2013-10-19
上传用户：1184599859
为解决我国水位监测野外条件下长期无人看守的问题，研制开发了基于MSP430单片机的智能水位计。从其组成到各功能分别进行了详细的介绍，该智能水位计不仅实现了水位数据的实时监测、记录和定期采集等多种工作模式，而且提高了水位监测精度，实现了水位监测的智能化。 Abstract: In order to solve the problems of LONG-term unmanned observation in the field water monitoring，an intelligence water-level meter based on MSP430 is developed composition and every function moduce of the water level meter was introduced in detail. It not only realizes water level data collection and storage， regularly gathering and so on， but also improves the water-level precision ， finally realizes the intelligence.
上传时间： 2013-11-17
上传用户：417313137
为提高温度测量效率，降低系统的成本，扩展传输距离，设计出一种新型温度采集系统。单片机通过控制具有单总线方式的温度传感器DS18B20实现对温度的测量，同时单片机通过控制具有单总线方式300～450MHz频率范围内的MAX7044与MAX7033无线发射与接收芯片实现温度数据的无线传输。与传统温度采集系统相比，该系统利用单总线方式连接，采用无线传输方式实现远距离通信，易于系统的集成与扩展。实验结果表明，该系统结构简单、方便移植，能够同时实现多达上百点温度的测量与500m范围的传输。 Abstract: To improve the temperature measurement efficiency and reduce system cost,expansion of transmission distance,a new type of temperature acquisition system is designed.Microcontroller controlled temperature sensor DS18B20which has a single-bus achieves temperature measurement,while microcontroller by controlled the MAX7044and MAX7033chip with a single-bus and having300~450MHz radiofrequency to achieve the wireless transmission of temperature data.Compared with conventional temperature acquisition system,the system uses single-bus connected,and uses wireless transmission means to achieve LONG-distance communications,easy-to-system integration and expansion.The experimental results show that the system is simple,convenient transplantation,and can be implemented in as many as a hundred-point temperature measure-ment and the transmission range of500meters.
上传时间： 2013-10-29
上传用户：515414293
阐述了一个由上位PC机和AT89C52下位单片机组成的主从分布式温度巡回检测系统。主从机采用RS-485 串行通讯标准进行通信，可在下位单片机实现基本的温度数据巡回检测基础上，由上位PC机实现综合处理功能或扩展为远程操作。整个系统具有巡检速度快，扩展性好的特点。 Abstract: In this paper,a top PC and AT89C52 under-bit microcontrollers from the main component of the tour distributed temperature detection system is presented. Master and slave can use RS-485 serial communication standards for communications.Based on next-bit machine for basic goods temperature detected data Tour, the top can achieve the integrated treatment of PC functions or for the expansion of LONG-distance operation. The entire inspection system is fast, expansion.
上传时间： 2013-10-12
上传用户：zhoujunzhen
